Wire mesh brush seal windage cover

ABSTRACT

Aspects of the disclosure are directed to a brush seal comprising: a first plate, a wire mesh adjacent the first plate, a bristle pack adjacent the wire mesh, and a second plate adjacent the bristle pack. Aspects of the disclosure are directed to a method comprising: positioning a wire mesh adjacent to a first plate, positioning a bristle pack adjacent to the wire mesh, positioning a second plate adjacent to the bristle pack, applying a toolset to hold the first plate, the wire mesh, the bristle pack, and the second plate in a stack-up, and performing an operation to form a brush seal from the stack-up of the first plate, the wire mesh, the bristle pack, and the second plate.

This application is a divisional of U.S. patent application Ser. No.15/092,793 filed Apr. 7, 2016, which is hereby incorporated herein byreference in its entirety.

BACKGROUND

Seals are used in an aircraft engine to isolate a fluid from one or moreareas/regions of the engine. For example, seals are used to controlvarious characteristics (e.g., temperature, pressure) withinareas/regions of the engine and ensure proper/efficient engine operationand stability. Brush seals are a type of seal that provides fluidisolation in the manner described above. A brush seal may be implementedas a bundle/package of bristles sandwiched between two plates.

The bristles may need to be protected. For example, if the bristles areexposed to an excitation (e.g., windage) a bristle may have a tendencyto become loose or even break-away from the bristle pack, in which casethe bristle may impact (e.g., clog) a downstream component.

Two types of covers are frequently used to protect the bristles of thebrush seal. A first type of cover is a plate cover. Plate covers arebulky, add weight, and present difficulties in terms of themanufacturability of the brush seal. A second type of cover is a sheetmetal cover. The sheet metal cover is thin and susceptible todegradation due to handling.

BRIEF SUMMARY

The following presents a simplified summary in order to provide a basicunderstanding of some aspects of the disclosure. The summary is not anextensive overview of the disclosure. It is neither intended to identifykey or critical elements of the disclosure nor to delineate the scope ofthe disclosure. The following summary merely presents some concepts ofthe disclosure in a simplified form as a prelude to the descriptionbelow.

Aspects of the disclosure are directed to a brush seal comprising: afirst plate, a wire mesh adjacent the first plate, a bristle packadjacent the wire mesh, and a second plate adjacent the bristle pack. Insome embodiments, the wire mesh is configured as a windage cover withrespect to the bristle pack. In some embodiments, the wire mesh isconfigured to protect the bristle pack with respect to an airflowassociated with an engine. In some embodiments, the airflow includesbleed air from a compressor section of the engine. In some embodiments,the wire mesh includes a metal alloy. In some embodiments, the wire meshhas a first length that is substantially equal to a third length of thebristle pack. In some embodiments, the wire mesh has a first length thatis substantially less than a third length of the bristle pack. In someembodiments, the wire mesh has a first length that is greater than asecond length of the second plate, and the first length is less than athird length of the bristle pack. In some embodiments, at least one ofthe bristle pack and the wire mesh includes a ceramic coat.

Aspects of the disclosure are directed to a method comprising:positioning a wire mesh adjacent to a first plate, positioning a bristlepack adjacent to the wire mesh, positioning a second plate adjacent tothe bristle pack, applying a toolset to hold the first plate, the wiremesh, the bristle pack, and the second plate in a stack-up, andperforming an operation to form a brush seal from the stack-up of thefirst plate, the wire mesh, the bristle pack, and the second plate. Insome embodiments, the operation includes electron beam welding. In someembodiments, the operation includes a welding that projects through atleast one of the first plate, the wire mesh, the bristle pack, and thesecond plate. In some embodiments, the operation includes a welding thatis performed along an end of the stack-up. In some embodiments, the endis substantially contiguous in relation to the first plate, the wiremesh, the bristle pack, and the second plate. In some embodiments, theoperation is performed in conjunction with the application of thetoolset. In some embodiments, the operation includes laser welding. Insome embodiments, the operation includes application of a mechanicalattachment technique. In some embodiments, the mechanical attachmenttechnique includes crimping

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example and not limitedin the accompanying drawing figures in which like reference numeralsindicate similar elements. The drawing figures are not necessarily drawnto scale unless specifically indicated otherwise.

FIG. 1 is a side cutaway illustration of a geared turbine engine.

FIG. 2A illustrates a brush seal in accordance with aspects of thisdisclosure.

FIG. 2B illustrates an arrangement of bristles within a bristle pack inaccordance with aspects of this disclosure.

FIG. 3A illustrates a seal arranged as a continuous structure inaccordance with aspects of this disclosure.

FIG. 3B illustrates a number of the seals arranged as a split-ring informing a sealing structure in accordance with aspects of thisdisclosure.

FIG. 4 illustrates a method for manufacturing a seal in accordance withaspects of this disclosure.

FIG. 5 illustrates an application of a toolset to form a seal inaccordance with aspects of this disclosure.

FIG. 6 illustrates a method for manufacturing a seal in accordance withaspects of this disclosure.

DETAILED DESCRIPTION

It is noted that various connections are set forth between elements inthe following description and in the drawings (the contents of which areincluded in this disclosure by way of reference). It is noted that theseconnections are general and, unless specified otherwise, may be director indirect and that this specification is not intended to be limitingin this respect. A coupling between two or more entities may refer to adirect connection or an indirect connection. An indirect connection mayincorporate one or more intervening entities.

In accordance with various aspects of the disclosure, apparatuses,systems and methods are described in connection with a seal configuredfor use on an engine. In some embodiments, a brush seal may include awire mesh windage cover. The wire mesh windage cover may help to protectone or more bristles of a bristle pack.

Aspects of the disclosure may be applied in connection with a gasturbine engine. FIG. 1 is a side cutaway illustration of a gearedturbine engine 10. This turbine engine 10 extends along an axialcenterline 12 between an upstream airflow inlet 14 and a downstreamairflow exhaust 16. The turbine engine 10 includes a fan section 18, acompressor section 19, a combustor section 20 and a turbine section 21.The compressor section 19 includes a low pressure compressor (LPC)section 19A and a high pressure compressor (HPC) section 19B. Theturbine section 21 includes a high pressure turbine (HPT) section 21Aand a low pressure turbine (LPT) section 21B.

The engine sections 18-21 are arranged sequentially along the centerline12 within an engine housing 22. Each of the engine sections 18-19B, 21Aand 21B includes a respective rotor 24-28. Each of these rotors 24-28includes a plurality of rotor blades arranged circumferentially aroundand connected to one or more respective rotor disks. The rotor blades,for example, may be formed integral with or mechanically fastened,welded, brazed, adhered and/or otherwise attached to the respectiverotor disk(s).

The fan rotor 24 is connected to a gear train 30, for example, through afan shaft 32. The gear train 30 and the LPC rotor 25 are connected toand driven by the LPT rotor 28 through a low speed shaft 33. The HPCrotor 26 is connected to and driven by the HPT rotor 27 through a highspeed shaft 34. The shafts 32-34 are rotatably supported by a pluralityof bearings 36; e.g., rolling element and/or thrust bearings. Each ofthese bearings 36 is connected to the engine housing 22 by at least onestationary structure such as, for example, an annular support strut.

During operation, air enters the turbine engine 10 through the airflowinlet 14, and is directed through the fan section 18 and into a core gaspath 38 and a bypass gas path 40. The air within the core gas path 38may be referred to as “core air”. The air within the bypass gas path 40may be referred to as “bypass air”. The core air is directed through theengine sections 19-21, and exits the turbine engine 10 through theairflow exhaust 16 to provide forward engine thrust. Within thecombustor section 20, fuel is injected into a combustion chamber 42 andmixed with compressed core air. This fuel-core air mixture is ignited topower the turbine engine 10. The bypass air is directed through thebypass gas path 40 and out of the turbine engine 10 through a bypassnozzle 44 to provide additional forward engine thrust. This additionalforward engine thrust may account for a majority (e.g., more than 70percent) of total engine thrust. Alternatively, at least some of thebypass air may be directed out of the turbine engine 10 through a thrustreverser to provide reverse engine thrust.

FIG. 1 represents one possible configuration for a geared gas turbineengine 10. Aspects of the disclosure may be applied in connection withother environments, including additional configurations for gas turbineengines. Aspects of the disclosure may be applied in connection with,e.g., turbojets, turboprops, low bypass ratio gas turbine engines, orhigh bypass ratio gas turbine engines. In some embodiments, aplatform/configuration may utilize multiple flow streams and/or thrustaugmentation. Any number of applications incorporating rotatingmachinery may incorporate aspects of this disclosure. Aspects of thedisclosure may be applied in connection with static hardware.

Referring now to FIG. 2A, a brush seal 200 is shown. The seal 200 may beincorporated as part of one or more sections of the engine, such as forexample the compressor section 19 or the turbine section 21 of theengine 10 of FIG. 1. In some embodiments, the seal 200 may be used tointerface a vane or a blade outer air seal (BOAS) of the engine 10. Insome embodiments, the seal 200 may be used to interface rotating andstatic structure (e.g., as part of a pairing of a rotor and stator).

Referring back to FIG. 2A, the seal 200 may include one or more plates,such as for example a top, first plate 202 and a bottom/backing, secondplate 212. The plates 202 and 212 may at least partially contain/house abristle pack 218. The bristle pack 218 may include a plurality ofwires/bristles. The seal 200 may include a wire mesh 252. The wire mesh252 may be configured as a windage cover with respect to the bristlepack 218 as described further below.

The wire mesh 252 is shown as being disposed between the bristle pack218 and the plate 202, adjacent to or along a surface of the bristlepack 218. Proceeding in a right-to-left manner in FIG. 2A, the seal 200may include a stack-up of the plate 202, the wire mesh 252, the bristlepack 218, and the plate 212.

The wire mesh 252 may be coupled to the bristle pack 218 during, e.g., awelding procedure/operation as described further below. The wire mesh252 may reduce/minimize, or even eliminate, an excitation of thebristles of the bristle pack 218 and provide additional sealingcapability. For example, the wire mesh 252 may help to protect thebristle pack 218 against an excitation/flow associated with thereference character/arrow 264 shown in FIG. 2A. The excitation/flow 264may be indicative of a compressor bleed air or any other secondaryairflow (where, for example, a primary airflow may pertain to an airflowinvolved in combustion within the engine 10 of FIG. 1).

The plate 202, the wire mesh 252, the bristle pack 218, and the plate212 may be made of one or more materials. For example, a metal alloy maybe used in the fabrication/construction of one or more of the plate 202,the wire mesh 252, the bristle pack 218, and the plate 212. The plate202 or the plate 212 may include Inconel® 625 or Inconel® 718 alloy. Thewire mesh 252 may include Inconel® 625.

The wire mesh 252 may have any thickness/width 252W that is suitable forthe given application/environment at hand. In connection with use in anaircraft engine, the width 252W may have a value within a range ofapproximately 0.004 inches (approximately 0.10 millimeters) toapproximately 0.060 inches (approximately 1.52 millimeters).

The wire mesh 252 may have a length 252L. The length 252L may besubstantially greater than, or even substantially equal to, a length212L of the plate 212. The length 252L may be substantially less than,or even substantially equal to, a length 218L of the bristle pack 218.Having the length 252L be less than the length 218L may help to avoidthe wire mesh 252 permanently bending in the presence of one or moreforces. For example, if the seal 200 is deployed in connection withrotating machinery (e.g., an engine),deformations/imperfections/deflections in a rotor may result in forcesthat may cause a shaft to come into contract with the bristle pack 218.Providing a clearance/gap between the wire mesh 252 and the bristle pack218 (illustratively in terms of the difference in their respectivelengths 252L and 218L) may aid in preserving the wire mesh 252.

The wire mesh 252 may have any number of candidate densities; theselection of a particular density may be based on theapplication/environment that the seal 200 is targeted to. A largerdensity (e.g., a tighter weave of the material used in the fabricationof the wire mesh 252) may make the wire mesh 252 stiffer and provideless flow area through the wire mesh 252.

To provide further environmental protection to the seal 200, one or moreportions of the seal 200 may include a coating. For example, the bristlepack 218 and/or the wire mesh 252 may include a ceramic coat, which mayenable the seal 200 to operate in environments having elevatedtemperatures.

The bristle pack 218 may include bristles having various types oforientations. For example, and referring to FIG. 2B, the bristle pack218 is shown as including a first plurality/multiple of bristles 218 aand a second plurality/multiple of bristles 218 b that are oriented atan angle (denoted by reference character 274) relative to the bristles218 a. The angle 274 may have a value within a range of 30 degrees and60 degrees. Any number of orientations (e.g., angles) may be used insome embodiments.

The seal 200 may be manufactured as a continuous structure (see FIG.3A). In such cases the overall shape of the seal may be a circle, anellipse, or may feature flat sides with full radius ends. In someembodiments, the seal 200 may be manufactured as a split-ring structurewhere the seal 200 may be configured to be incorporated as part of ahoop or ring. For example, referring to FIG. 3B multiple seals 200 maybe used to form a larger sealing structure 350.

Referring to FIG. 4, a flowchart of a method 400 is shown. The method400 may be used to fabricate/manufacture a seal. The method 400 isdescribed in the context of the seal 200, but it is understood that themethod 400 may be adapted to accommodate other seals.

In block 404, a bristle pack (e.g., bristle pack 218) may be coupled toa first plate (e.g., plate 212). For example, as part of block 404 thebristle pack may be positioned adjacent to the first plate as shown inFIG. 2A.

In block 410, a wire mesh (e.g., wire mesh 252) may be coupled to thebristle pack. For example, as part of block 410 the wire mesh may bepositioned adjacent to the bristle pack as shown in FIG. 2A.

In block 416, a second plate (e.g., plate 202) may be coupled to thewire mesh. For example, as part of block 416 the second plate may bepositioned adjacent to the wire mesh as shown in FIG. 2A.

In block 422, a toolset (illustrated schematically via referencecharacter 510 in FIG. 5) may be applied to the stack-up/coupling oflayers obtained in blocks 404-416 as described above. The toolset 510may be used to hold the layers 202, 252, 218, and 212 together or in apositional relationship/stack-up relative to one another, for examplebased on an application of force to the layers 202, 252, 218, and 212.Still further, the toolset 510 may cool one or more of the plate 202,the wire mesh 252, the bristle pack 218, or the plate 212. While theapplication of the toolset 510 is referred to in a separate block 422 inFIG. 4, in accordance with aspects of the disclosure the toolset 510 maybe applied as part of one or more of the blocks 404-416.

In block 428, a welding operation may occur along an end/surface 522 ofthe stack-up of the plate 202, 252, 218, and 212. For ease ofmanufacture, the end/surface 522 may be substantially smooth/contiguouswith respect to the stack-up of the layers 202, 252, 218, and 212. Insome embodiments, a welding operation may project through one or more ofthe layers 202, 252, 218, and 212 as denoted via arrow/referencecharacter 534. The operation of block 428 may include electron beam (EB)welding or laser welding. Moreover, the operation of block 428 mayinclude attachment/securing of the wire mesh via mechanical techniques(e.g., crimping). While shown as a separate block, the operation ofblock 428 may be performed in conjunction with the application of thetoolset in block 422 in some embodiments.

FIG. 6 illustrates a flowchart of a method 600 that may be used tofabricate/manufacture a seal. The method 600 is described in the contextof the seal 200, but it is understood that the method 600 may be adaptedto accommodate other seals.

In block 602, a wire mesh (e.g., wire mesh 252) may be positionedadjacent to a first plate (e.g., plate 202).

In block 608, a bristle pack (e.g., bristle pack 218) may be positionedadjacent to the wire mesh.

In block 614, a second plate (e.g., plate 212) may be positionedadjacent to the bristle pack.

In block 620, a toolset (toolset 510 of FIG. 5) may be applied to holdthe first plate, the wire mesh, the bristle pack, and the second platein a stack-up. Application of the toolset 620 may provide similarfeatures/functionality as described above in connection with block 422.

In block 626, an operation may be performed to form a brush seal. Theoperation of block 626 may include welding and/or mechanical attachmenttechniques similar to what is described above in connection with block428.

The blocks of the methods 400 and 600 are illustrative. In someembodiments the blocks/operations may occur in an order/sequence that isdifferent from what is shown in FIG. 4 or FIG. 6. In some embodiments,additional blocks/operations not shown may be included. At least some ofthe blocks/operations of the methods 400 and 600 may be combined in someembodiments.

Technical effects and benefits of this disclosure include a seal thatmay be incorporated as part of one or more sections of an engine.Relative to a conventional seal, a seal in accordance with thisdisclosure may include a windage cover that facilitates ease in themanufacture of the seal. Furthermore, aspects of the disclosure providea light weight seal while increasing the reliability of the seal interms of use/deployment by preserving the structural integrity of theseal (e.g., the bristle pack).

Aspects of the disclosure have been described in terms of illustrativeembodiments thereof. Numerous other embodiments, modifications, andvariations within the scope and spirit of the appended claims will occurto persons of ordinary skill in the art from a review of thisdisclosure. For example, one of ordinary skill in the art willappreciate that the steps described in conjunction with the illustrativefigures may be performed in other than the recited order, and that oneor more steps illustrated may be optional in accordance with aspects ofthe disclosure. One or more features described in connection with afirst embodiment may be combined with one or more features of one ormore additional embodiments.

What is claimed is:
 1. A method comprising: positioning a wire meshadjacent to a first plate; positioning a bristle pack adjacent to thewire mesh; positioning a second plate adjacent to the bristle pack;applying a toolset to hold the first plate, the wire mesh, the bristlepack, and the second plate in a stack-up; and performing an operation toform a brush seal from the stack-up of the first plate, the wire mesh,the bristle pack, and the second plate.
 2. The method of claim 1,wherein the operation includes electron beam welding.
 3. The method ofclaim 1, wherein the operation includes a welding that projects throughat least one of the first plate, the wire mesh, the bristle pack, andthe second plate.
 4. The method of claim 1, wherein the operationincludes a welding that is performed along an end of the stack-up. 5.The method of claim 4, wherein the end is substantially contiguous inrelation to the first plate, the wire mesh, the bristle pack, and thesecond plate.
 6. The method of claim 1, wherein the operation isperformed in conjunction with the application of the toolset.
 7. Themethod of claim 1, wherein the operation includes laser welding.
 8. Themethod of claim 1, wherein the operation includes application of amechanical attachment technique.
 9. The method of claim 8, wherein themechanical attachment technique includes crimping.